His sister skirted death, but survived. She is living proof, her mother says, of what can happen when otherwise responsible gun owners have a safety lapse.

Receive the latest national-international updates in your inbox

In this April 14, 2016 photo, Denise Kirchner and her daughter, Madison, right, talk about an accidental shooting a few days before Thanksgiving 2015, in their home in Toledo, Iowa. Madison and her older brother, Dylan, were cleaning guns when one accidentally discharged. A bullet passed through Madison’s left breast, narrowly missing her spine but leaving six holes in her stomach and intestines. It then passed through Denise’s thigh before ending up in a cupboard. (AP Photo/Charlie Neibergall)

They were, says Denise Kirchner, "the worst three hours of my life" — the agonizing moments after her son accidentally shot her and her 14-year-old daughter Madison while cleaning his semi-automatic gun in their Iowa home.

Madison skirted death, but survived. She is living proof, her mother says, of what can happen when otherwise responsible gun owners have a safety lapse.

Dylan, 18, had been trying to remove bullets from the chamber of the .40-caliber handgun when it fired, Toledo Police Chief Bob Kendall said. The bullet passed through the left breast of his younger sister Madison, narrowly missing her spine but leaving six holes in her stomach and intestines. It then passed through the thigh of Denise, who was at her kitchen sink doing dishes, before lodging in a cupboard.

The accidental shooting last November was one of three involving minors in their rural Iowa county in roughly a year's time; the others ended in deaths for two teenage girls.

The cases also were among more than 1,000 accidental shootings involving minors nationwide over a 2½-year period. The Associated Press and the USA TODAY Network analyzed every such shooting and found that the official tally kept by the federal government undercounts the problem by roughly a third.

Emergency responders came quickly and rushed the daughter and mother to a hospital about 20 miles away. Denise Kirchner's injuries turned out to be minor, but doctors told her Madison would not survive the 17-minute flight to a children's hospital in Des Moines and had to undergo surgery immediately.

The high school freshman still suffers from an occasional stomach bleed, has trouble sleeping and is trying to catch up on the weeks of school she missed. But Kendall, the police chief, said it's amazing she survived.

The chief recently brought the girl the bullet, which she might put on a necklace.